Assuming the HCl solution has the same specific heat capacity as water (this is a quite reasonable assumption, as it turns out) calculate the heat flow (in J) for the solution Remember to use proper sign conventions
The Correct Answer and Explanation is:
To calculate the heat flow (Q) for the HCl solution, we can use the equation for heat transfer:Q=mcΔTQ = mc\Delta TQ=mcΔT
Where:
- QQQ is the heat flow (in Joules),
- mmm is the mass of the solution (in kg),
- ccc is the specific heat capacity of the solution (in J/kg·K),
- ΔT\Delta TΔT is the change in temperature (in °C or K).
Step 1: Assumptions and Given Data
We are told to assume that the specific heat capacity of the HCl solution is the same as that of water, which is approximately:c=4186 J/kg\cdotpKc = 4186 \, \text{J/kg·K}c=4186J/kg\cdotpK
Next, we need the mass of the solution and the change in temperature. If the solution’s mass mmm and temperature change ΔT\Delta TΔT are not given, we would need that information to proceed. In this case, let’s assume the mass of the solution is 1 kg and the temperature change is 10°C (as an example).m=1 kg,ΔT=10∘Cm = 1 \, \text{kg}, \quad \Delta T = 10^\circ Cm=1kg,ΔT=10∘C
Step 2: Calculate the Heat Flow
Now, we can substitute the values into the equation:Q=(1 kg)×(4186 J/kg\cdotpK)×(10∘C)Q = (1 \, \text{kg}) \times (4186 \, \text{J/kg·K}) \times (10^\circ C)Q=(1kg)×(4186J/kg\cdotpK)×(10∘C)Q=41,860 JQ = 41,860 \, \text{J}Q=41,860J
Thus, the heat flow is 41,860 J.
Step 3: Consider the Sign Convention
If the temperature of the solution increases (endothermic process), the heat flow QQQ is positive, as heat is being absorbed by the system. Conversely, if the temperature decreases (exothermic process), the heat flow QQQ is negative, as heat is being released.
If, in this case, the temperature increase is assumed, then the heat flow is:Q=+41,860 JQ = +41,860 \, \text{J}Q=+41,860J
Conclusion:
The heat flow for the solution, assuming a 1 kg mass and a 10°C temperature change, is +41,860 J+41,860 \, \text{J}+41,860J, indicating heat was absorbed by the solution.
